Start 1.31.0 development cycle (#7050)

diff --git a/build.gradle b/build.gradle
index 8008239..f97ce5b 100644
--- a/build.gradle
+++ b/build.gradle
@@ -19,7 +19,7 @@
     apply plugin: "net.ltgt.errorprone"
 
     group = "io.grpc"
-    version = "1.30.0-SNAPSHOT" // CURRENT_GRPC_VERSION
+    version = "1.31.0-SNAPSHOT" // CURRENT_GRPC_VERSION
 
     repositories {
         maven { // The google mirror is less flaky than mavenCentral()
diff --git a/compiler/src/test/golden/TestDeprecatedService.java.txt b/compiler/src/test/golden/TestDeprecatedService.java.txt
index dd5e771..878e975 100644
--- a/compiler/src/test/golden/TestDeprecatedService.java.txt
+++ b/compiler/src/test/golden/TestDeprecatedService.java.txt
@@ -21,7 +21,7 @@
  * </pre>
  */
 @javax.annotation.Generated(
-    value = "by gRPC proto compiler (version 1.30.0-SNAPSHOT)",
+    value = "by gRPC proto compiler (version 1.31.0-SNAPSHOT)",
     comments = "Source: grpc/testing/compiler/test.proto")
 @java.lang.Deprecated
 public final class TestDeprecatedServiceGrpc {
diff --git a/compiler/src/test/golden/TestService.java.txt b/compiler/src/test/golden/TestService.java.txt
index 55773f6..7237937 100644
--- a/compiler/src/test/golden/TestService.java.txt
+++ b/compiler/src/test/golden/TestService.java.txt
@@ -21,7 +21,7 @@
  * </pre>
  */
 @javax.annotation.Generated(
-    value = "by gRPC proto compiler (version 1.30.0-SNAPSHOT)",
+    value = "by gRPC proto compiler (version 1.31.0-SNAPSHOT)",
     comments = "Source: grpc/testing/compiler/test.proto")
 public final class TestServiceGrpc {
 
diff --git a/compiler/src/testLite/golden/TestDeprecatedService.java.txt b/compiler/src/testLite/golden/TestDeprecatedService.java.txt
index 9e25eeb..1f3752b 100644
--- a/compiler/src/testLite/golden/TestDeprecatedService.java.txt
+++ b/compiler/src/testLite/golden/TestDeprecatedService.java.txt
@@ -21,7 +21,7 @@
  * </pre>
  */
 @javax.annotation.Generated(
-    value = "by gRPC proto compiler (version 1.30.0-SNAPSHOT)",
+    value = "by gRPC proto compiler (version 1.31.0-SNAPSHOT)",
     comments = "Source: grpc/testing/compiler/test.proto")
 @java.lang.Deprecated
 public final class TestDeprecatedServiceGrpc {
diff --git a/compiler/src/testLite/golden/TestService.java.txt b/compiler/src/testLite/golden/TestService.java.txt
index 07c5837..26621d1 100644
--- a/compiler/src/testLite/golden/TestService.java.txt
+++ b/compiler/src/testLite/golden/TestService.java.txt
@@ -21,7 +21,7 @@
  * </pre>
  */
 @javax.annotation.Generated(
-    value = "by gRPC proto compiler (version 1.30.0-SNAPSHOT)",
+    value = "by gRPC proto compiler (version 1.31.0-SNAPSHOT)",
     comments = "Source: grpc/testing/compiler/test.proto")
 public final class TestServiceGrpc {
 
diff --git a/core/src/main/java/io/grpc/internal/GrpcUtil.java b/core/src/main/java/io/grpc/internal/GrpcUtil.java
index f6cac53..2a2b0e6 100644
--- a/core/src/main/java/io/grpc/internal/GrpcUtil.java
+++ b/core/src/main/java/io/grpc/internal/GrpcUtil.java
@@ -196,7 +196,7 @@
 
   public static final Splitter ACCEPT_ENCODING_SPLITTER = Splitter.on(',').trimResults();
 
-  private static final String IMPLEMENTATION_VERSION = "1.30.0-SNAPSHOT"; // CURRENT_GRPC_VERSION
+  private static final String IMPLEMENTATION_VERSION = "1.31.0-SNAPSHOT"; // CURRENT_GRPC_VERSION
 
   /**
    * The default timeout in nanos for a keepalive ping request.
diff --git a/examples/android/clientcache/app/build.gradle b/examples/android/clientcache/app/build.gradle
index 108bbda..81401f3 100644
--- a/examples/android/clientcache/app/build.gradle
+++ b/examples/android/clientcache/app/build.gradle
@@ -30,7 +30,7 @@
 protobuf {
     protoc { artifact = 'com.google.protobuf:protoc:3.11.0' }
     plugins {
-        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
         }
     }
     generateProtoTasks {
@@ -50,12 +50,12 @@
     implementation 'com.android.support:appcompat-v7:27.0.2'
 
     // You need to build grpc-java to obtain these libraries below.
-    implementation 'io.grpc:grpc-okhttp:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-protobuf-lite:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-stub:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-okhttp:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-protobuf-lite:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-stub:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
     implementation 'org.apache.tomcat:annotations-api:6.0.53'
 
     testImplementation 'junit:junit:4.12'
     testImplementation 'com.google.truth:truth:1.0.1'
-    testImplementation 'io.grpc:grpc-testing:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    testImplementation 'io.grpc:grpc-testing:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 }
diff --git a/examples/android/helloworld/app/build.gradle b/examples/android/helloworld/app/build.gradle
index 332954b..5ec43e4 100644
--- a/examples/android/helloworld/app/build.gradle
+++ b/examples/android/helloworld/app/build.gradle
@@ -29,7 +29,7 @@
 protobuf {
     protoc { artifact = 'com.google.protobuf:protoc:3.11.0' }
     plugins {
-        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
         }
     }
     generateProtoTasks {
@@ -49,8 +49,8 @@
     implementation 'com.android.support:appcompat-v7:27.0.2'
 
     // You need to build grpc-java to obtain these libraries below.
-    implementation 'io.grpc:grpc-okhttp:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-protobuf-lite:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-stub:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-okhttp:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-protobuf-lite:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-stub:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
     implementation 'org.apache.tomcat:annotations-api:6.0.53'
 }
diff --git a/examples/android/routeguide/app/build.gradle b/examples/android/routeguide/app/build.gradle
index 4b0dd53..aa8b8e3 100644
--- a/examples/android/routeguide/app/build.gradle
+++ b/examples/android/routeguide/app/build.gradle
@@ -28,7 +28,7 @@
 protobuf {
     protoc { artifact = 'com.google.protobuf:protoc:3.11.0' }
     plugins {
-        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
         }
     }
     generateProtoTasks {
@@ -48,8 +48,8 @@
     implementation 'com.android.support:appcompat-v7:27.0.2'
 
     // You need to build grpc-java to obtain these libraries below.
-    implementation 'io.grpc:grpc-okhttp:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-protobuf-lite:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-stub:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-okhttp:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-protobuf-lite:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-stub:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
     implementation 'org.apache.tomcat:annotations-api:6.0.53'
 }
diff --git a/examples/android/strictmode/app/build.gradle b/examples/android/strictmode/app/build.gradle
index 601b2fb..f070cc9 100644
--- a/examples/android/strictmode/app/build.gradle
+++ b/examples/android/strictmode/app/build.gradle
@@ -29,7 +29,7 @@
 protobuf {
     protoc { artifact = 'com.google.protobuf:protoc:3.11.0' }
     plugins {
-        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
         }
     }
     generateProtoTasks {
@@ -49,8 +49,8 @@
     implementation 'com.android.support:appcompat-v7:28.0.0'
 
     // You need to build grpc-java to obtain these libraries below.
-    implementation 'io.grpc:grpc-okhttp:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-protobuf-lite:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-stub:1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-okhttp:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-protobuf-lite:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+    implementation 'io.grpc:grpc-stub:1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
     implementation 'org.apache.tomcat:annotations-api:6.0.53'
 }
diff --git a/examples/build.gradle b/examples/build.gradle
index 839db31..e92723d 100644
--- a/examples/build.gradle
+++ b/examples/build.gradle
@@ -22,7 +22,7 @@
 
 // Feel free to delete the comment at the next line. It is just for safely
 // updating the version in our release process.
-def grpcVersion = '1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+def grpcVersion = '1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 def protobufVersion = '3.11.0'
 def protocVersion = protobufVersion
 
diff --git a/examples/example-alts/build.gradle b/examples/example-alts/build.gradle
index 84e37df..0c7f9f4 100644
--- a/examples/example-alts/build.gradle
+++ b/examples/example-alts/build.gradle
@@ -23,7 +23,7 @@
 
 // Feel free to delete the comment at the next line. It is just for safely
 // updating the version in our release process.
-def grpcVersion = '1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+def grpcVersion = '1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 def protocVersion = '3.11.0'
 
 dependencies {
diff --git a/examples/example-gauth/build.gradle b/examples/example-gauth/build.gradle
index b556de8..93de596 100644
--- a/examples/example-gauth/build.gradle
+++ b/examples/example-gauth/build.gradle
@@ -23,7 +23,7 @@
 
 // Feel free to delete the comment at the next line. It is just for safely
 // updating the version in our release process.
-def grpcVersion = '1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+def grpcVersion = '1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 def protobufVersion = '3.11.0'
 def protocVersion = protobufVersion
 
diff --git a/examples/example-gauth/pom.xml b/examples/example-gauth/pom.xml
index 70f8ebe..3344bf8 100644
--- a/examples/example-gauth/pom.xml
+++ b/examples/example-gauth/pom.xml
@@ -6,13 +6,13 @@
   <packaging>jar</packaging>
   <!-- Feel free to delete the comment at the end of these lines. It is just
        for safely updating the version in our release process. -->
-  <version>1.30.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
+  <version>1.31.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
   <name>example-gauth</name>
   <url>https://github.com/grpc/grpc-java</url>
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <grpc.version>1.30.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
+    <grpc.version>1.31.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
     <protobuf.version>3.11.0</protobuf.version>
     <!-- required for jdk9 -->
     <maven.compiler.source>1.7</maven.compiler.source>
diff --git a/examples/example-hostname/build.gradle b/examples/example-hostname/build.gradle
index 8a521b4..e3abf6e 100644
--- a/examples/example-hostname/build.gradle
+++ b/examples/example-hostname/build.gradle
@@ -21,7 +21,7 @@
 
 // Feel free to delete the comment at the next line. It is just for safely
 // updating the version in our release process.
-def grpcVersion = '1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+def grpcVersion = '1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 def protobufVersion = '3.11.0'
 
 dependencies {
diff --git a/examples/example-hostname/pom.xml b/examples/example-hostname/pom.xml
index e26da43..df15841 100644
--- a/examples/example-hostname/pom.xml
+++ b/examples/example-hostname/pom.xml
@@ -6,13 +6,13 @@
   <packaging>jar</packaging>
   <!-- Feel free to delete the comment at the end of these lines. It is just
        for safely updating the version in our release process. -->
-  <version>1.30.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
+  <version>1.31.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
   <name>example-hostname</name>
   <url>https://github.com/grpc/grpc-java</url>
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <grpc.version>1.30.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
+    <grpc.version>1.31.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
     <protoc.version>3.11.0</protoc.version>
     <!-- required for jdk9 -->
     <maven.compiler.source>1.7</maven.compiler.source>
diff --git a/examples/example-jwt-auth/build.gradle b/examples/example-jwt-auth/build.gradle
index 366cb8d..1dc1a50 100644
--- a/examples/example-jwt-auth/build.gradle
+++ b/examples/example-jwt-auth/build.gradle
@@ -22,7 +22,7 @@
 
 // Feel free to delete the comment at the next line. It is just for safely
 // updating the version in our release process.
-def grpcVersion = '1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+def grpcVersion = '1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 def protobufVersion = '3.11.0'
 def protocVersion = protobufVersion
 
diff --git a/examples/example-jwt-auth/pom.xml b/examples/example-jwt-auth/pom.xml
index c5223cb..977a326 100644
--- a/examples/example-jwt-auth/pom.xml
+++ b/examples/example-jwt-auth/pom.xml
@@ -7,13 +7,13 @@
   <packaging>jar</packaging>
   <!-- Feel free to delete the comment at the end of these lines. It is just
        for safely updating the version in our release process. -->
-  <version>1.30.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
+  <version>1.31.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
   <name>example-jwt-auth</name>
   <url>https://github.com/grpc/grpc-java</url>
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <grpc.version>1.30.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
+    <grpc.version>1.31.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
     <protobuf.version>3.11.0</protobuf.version>
     <protoc.version>3.11.0</protoc.version>
     <!-- required for jdk9 -->
diff --git a/examples/example-tls/build.gradle b/examples/example-tls/build.gradle
index 458010c..3e0608a 100644
--- a/examples/example-tls/build.gradle
+++ b/examples/example-tls/build.gradle
@@ -23,7 +23,7 @@
 
 // Feel free to delete the comment at the next line. It is just for safely
 // updating the version in our release process.
-def grpcVersion = '1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+def grpcVersion = '1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 def nettyTcNativeVersion = '2.0.30.Final'
 def protocVersion = '3.11.0'
 
diff --git a/examples/example-tls/pom.xml b/examples/example-tls/pom.xml
index db22206..f00ad35 100644
--- a/examples/example-tls/pom.xml
+++ b/examples/example-tls/pom.xml
@@ -6,13 +6,13 @@
   <packaging>jar</packaging>
   <!-- Feel free to delete the comment at the end of these lines. It is just
        for safely updating the version in our release process. -->
-  <version>1.30.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
+  <version>1.31.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
   <name>example-tls</name>
   <url>https://github.com/grpc/grpc-java</url>
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <grpc.version>1.30.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
+    <grpc.version>1.31.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
     <protoc.version>3.11.0</protoc.version>
     <netty.tcnative.version>2.0.30.Final</netty.tcnative.version>
     <!-- required for jdk9 -->
diff --git a/examples/example-xds/build.gradle b/examples/example-xds/build.gradle
index b8ed5d6..28e3463 100644
--- a/examples/example-xds/build.gradle
+++ b/examples/example-xds/build.gradle
@@ -18,7 +18,7 @@
 
 // Feel free to delete the comment at the next line. It is just for safely
 // updating the version in our release process.
-def grpcVersion = '1.30.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+def grpcVersion = '1.31.0-SNAPSHOT' // CURRENT_GRPC_VERSION
 
 dependencies {
     // This example's client is the same as the helloworld client. We depend on the helloworld
diff --git a/examples/pom.xml b/examples/pom.xml
index de93df2..18b3505 100644
--- a/examples/pom.xml
+++ b/examples/pom.xml
@@ -6,13 +6,13 @@
   <packaging>jar</packaging>
   <!-- Feel free to delete the comment at the end of these lines. It is just
        for safely updating the version in our release process. -->
-  <version>1.30.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
+  <version>1.31.0-SNAPSHOT</version><!-- CURRENT_GRPC_VERSION -->
   <name>examples</name>
   <url>https://github.com/grpc/grpc-java</url>
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <grpc.version>1.30.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
+    <grpc.version>1.31.0-SNAPSHOT</grpc.version><!-- CURRENT_GRPC_VERSION -->
     <protobuf.version>3.11.0</protobuf.version>
     <protoc.version>3.11.0</protoc.version>
     <!-- required for jdk9 -->